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Biomedical subjects

J Ferguson

Publications and source records attributed to J Ferguson.

At least 235 records · Page 13Linked to original sources
PubMed1991

Transplacental passage of mifepristone and its influence on maternal and fetal steroid concentrations in the second trimester of pregnancy.

The maternal and fetal endocrine effects of the maternal administration of the anti-progestin mifepristone in mid-pregnancy have been investigated. Mifepristone and the metabolite RU 42,633 were detected in the fetal circulation and in the amniotic fluid 4, 24 and 48 h after oral ingestion. Maximum fetal plasma concentrations of mifepristone occurred 4 h after treatment indicating rapid placental transfer of the drug. No significant changes in progesterone, cortisol, oestradiol or aldosterone concentrations were detected in the maternal circulation after mifepristone treatment. No significant changes occurred in the fetal progesterone, oestradiol or cortisol concentrations, but a significant increase in fetal aldosterone occurred 4 and 24 h after treatment. The significance of these results is discussed in relation to the possible therapeutic uses of mifepristone for inducing labour.

Abortion, Induced↗
PubMed1991

Application of portfolio theory in decision tree analysis.

A general application of portfolio analysis for herd decision tree analysis is described. In the herd environment, this methodology offers a means of employing population-based decision strategies that can help the producer control economic variation in expected return from a given set of decision options. An economic decision tree model regarding the use of prostaglandin in dairy cows with undetected estrus was used to determine the expected return of the decisions to use prostaglandin and breed on a timed basis, use prostaglandin and then breed on sign of estrus, or breed on signs of estrus. The risk attributes of these decision alternatives were calculated from the decision tree, and portfolio theory was used to find the efficient decision combinations (portfolios with the highest return for a given variance). The resulting combinations of decisions could be used to control return variation.

Animals↗
PubMed1991

A comparison of cetirizine and terfenadine in the management of solar urticaria.

Many solar urticaria patients may benefit from the use of antihistamines. Historically, the value of such therapy was limited by sedation. Newer agents such as terfenadine and cetirizine that are relatively non-sedating appear to be better tolerated by patients. The latter drug, in addition to its antihistamine effect, also appears to inhibit eosinophil migration, which terfenadine and other potent H1 antagonists do not significantly affect. Eosinophils have been reported as early migrating cells in induced solar urticaria, raising the possibility that the dual action of cetirizine may provide a greater potential benefit in the management of solar urticaria. Six patients with idiopathic solar urticaria were entered into a double-blind, phototest study to compare cetirizine and terfenadine. Using the minimal urticarial dose as a phototest end-point, both drugs were equally effective in raising the threshold of sensitivity in 4 patients. Two patients failed to respond to either therapy, which is in keeping with the known variable response to histamine blockade in solar urticaria. At the dosage used, cetirizine therapy appears to be no more effective than terfenadine.

Adult↗
PubMed1990

Cigarette smoking, blast crisis, and survival in chronic myeloid leukemia.

We reviewed the records of all patients with chronic myeloid leukemia (CML) seen in the CML Clinic of the University of Colorado Health Sciences Center between 1968 and 1987 for a history of cigarette smoking. Patients who smoked for five or more pack/years within the ten years preceding, or after the diagnosis of CML, were defined as smokers. Adequate smoking histories were obtained on 122 patients. Eighty-seven of these were non-smokers and 35 were smokers by the above criteria. The smoking group had a higher predominance of males, an older median age, and were diagnosed earlier in the course of the 20 year study. Seventy-two patients had died at the time of analysis. All but one, a non-smoker, died from the development of blast crisis. The overall median actuarial survival was significantly reduced for smokers (35 months) as compared to non-smokers (47 months). This was particularly striking for patients who had succumbed to the disease, with a median survival of 30 months in smokers versus 46 months in non-smokers. Although various explanations could explain the differences noted, we conclude that cigarette smoking has an adverse effect on the development of blast crisis and survival in chronic myeloid leukemia.

Adolescent↗
PubMed1990

The efficacy of oral Mifepristone (RU 38,486) with a prostaglandin E1 analog vaginal pessary for the termination of early pregnancy: complications and patient acceptability.

Outpatient terminations were performed on 100 ultrasonographically confirmed pregnancies of less than or equal to 63 days with a single oral dose of RU 38,486 (600 mg) and a single vaginal pessary of 16,16-dimethyl-trans-delta 2-prostaglandin E1 (1 mg) 48 hours later. Abortion occurred in all patients; in 95 it was complete, in four it was incomplete, and one resulted in a missed abortion. In 88% the abortion occurred within 4 hours of prostaglandin treatment. A total of 25% of patients had nausea and 15% vomited after RU 38,486 treatment. After prostaglandin-treatment, 13% vomited, 10% had diarrhea, and 23% required administration of an opiate analgesic agent. No patient was transfused and there was no genital tract trauma; one case of suspected pelvic infection occurred. If the need for termination arose again, 88% would elect to use the method again, 9% would not. The combination of the antiprogestin RU 38,486 and a vaginal prostaglandin pessary appears to offer a safe, efficient, acceptable nonsurgical outpatient method of termination. Further studies on dosage and treatment protocols would be justified.

Abortifacient Agents↗
PubMed1990

The loss of antibiotic activity of ciprofloxacin by photodegradation.

Solutions of ciprofloxacin were irradiated with different wavebands of ultraviolet and visible radiation and the antibiotic activity of the drug was determined against Escherichia coli. A wavelength dependent loss of antibiotic activity was found with maximal effect around 320 nm; no effect occurred with visible irradiation. The degree of the decrease in activity with longer wavelength ultraviolet (UVA) radiation was sufficient to indicate that human exposure to sunlight through window glass (greater than 320 nm) or UVA from tanning sunbeds may result in a significant reduction in both cutaneous and circulating levels of ciprofloxacin.

Ciprofloxacin↗
PubMed1990

Ciprofloxacin-induced photosensitivity: in vitro and in vivo studies.

Ciprofloxacin is one of the new series of broad-spectrum antibiotic quinolones, chemically related to nalidixic acid and which may, therefore, induce photosensitization of human skin. Three in vitro tests for phototoxicity: the destruction of histidine, killing of mouse peritoneal macrophages and inhibition of PHA-stimulated DNA synthesis in human lymphocytes have demonstrated this photosensitizing potential with UVA irradiation at an order of magnitude lower than that for nalidixic acid. The Candida albicans test and photohaemolysis were negative. Controlled irradiation monochromator phototesting of 12 subjects, before, during and after taking ciprofloxacin showed subclinical photosensitivity with significantly lowered minimal 24 h erythema doses at 335 +/- 30 nm, 365 +/- 30 nm and 400 +/- 30 nm but not at 305 +/- 5 nm or above 400 +/- 30 nm.

Adult↗
PubMed1990

The placental transfer of mifepristone (RU 486) during the second trimester and its influence upon maternal and fetal steroid concentrations.

A double-blind, placebo-controlled study has assessed the maternal and fetal endocrine effects of the maternal administration of the anti-progestin mifepristone in mid-pregnancy. There were six women in each group. Four hours after oral administration of 600 mg mifepristone, the drug was detected in both maternal and fetal circulations and in the amniotic fluid. No significant changes in progesterone, cortisol, oestradiol, or aldosterone concentrations were detected in the maternal circulation after treatment with mifepristone or placebo. In women treated with mifepristone, the mean fetal aldosterone level was 1699 (SD 217) pmol/l which was significantly higher than the mean level of 999 (SD 84) pmol/l in the control group but no significant changes occurred in the fetal progesterone, oestradiol or cortisol concentrations. The significance of these results is discussed in relation to the possible therapeutic uses of mifepristone for inducing labour.

Aldosterone↗
PubMed1990

The physiological and clinical effects of progesterone inhibition with mifepristone (RU 486) in the second trimester.

A double-blind placebo-controlled trial was performed in 20 primigravidae to assess the physiological and clinical effects of oral mifepristone on myometrial contractility and sensitivity in the second trimester. Ten women received 600 mg of oral mifepristone and 10 women a placebo 24 h before abortion was induced in both groups, with extra-amniotic PGE2 instillation. Intrauterine pressure recordings demonstrated increased spontaneous uterine activity and increased sensitivity to PGE2 and ergometrine, but no change in oxytocin sensitivity after mifepristone treatment. There were no significant differences in PGE or PGF metabolite concentrations in peripheral maternal plasma over the 24-h study period after treatment between the mifepristone and placebo groups. The mean induction abortion interval in the mifepristone group was 512 (SD 321) min compared with 1128 (SD 606) min in the placebo group (P less than or equal to 0.02). The mechanism whereby mifepristone provokes enhanced uterine contractility and sensitivity to prostaglandins, with a reduction in abortion times, does not appear to be through endogenous production of PGE or PGF.

Abortion, Induced↗
PubMed1990

The effect of the anti-progestin mifepristone (RU 486) on plasma prostaglandin metabolite levels in early pregnancy and its influence on pregnancy termination.

The effect of a single dose of RU 486 (600mg) on prostaglandin metabolite levels has been studied over a 48 h period in 20 women undergoing medical termination of early pregnancy. The results were compared with controls of similar gestation who were treated surgically. The mean (SD) PGEM levels at 0 and 48 h in the RU 486 group were 13.7 (2.7) and 13.2 (2.2) pg/ml respectively, which was not significantly different from the values of 11.7 (1.1) and 11.3 (0.4) pg/ml measured in the control patients. Similarly the mean (SD) PGFM values of 22.3 (14.7) and 17.0 (7.2) pg/ml at 0 and 48 h were not significantly different from the corresponding control values of 21.9 (13.8) and 23.8 (7.2) pg/ml. In 10 of the study patients, there were no significant changes in PGEM and PGFM concentrations prior to and at 4, 24 and 48 h after RU 486 administration. Although all pregnancies were successfully terminated with the combination of RU 486 and subsequently a vaginal pessary containing PGE1, no stimulation of prostaglandin production could be demonstrated.

Abortion, Induced↗
PubMed1990

Anchoring fibrils and type VII collagen in human breast.

A correlated ultrastructural and immunofluorescent study of anchoring fibrils and their principal constituent, type VII collagen, has been carried out on lobular epithelium from the normal adult human breast at different times in the menstrual cycle. Throughout the cycle, characteristic, cross-banded anchoring fibrils were seen inserting into the area of lamina densa opposite the myoepithelial hemi-desmosomes and in contact with anchoring-plaques. Strong immunofluorescent staining was seen in the full thickness of the zone between the basement membrane and the delimiting fibroblasts. The data establish anchoring fibrils and their type VII collagen nature as readily identifiable components of the epithelial-stromal interface in breast tissues and their significance, especially in the diagnostic context, is discussed.

Breast↗
PubMed1990

Drug and chemical photosensitivity.

Chemical (especially drug-induced) cutaneous photo-sensitization is an increasing problem in dermatology. Various molecular, biochemical, and pathophysiologic processes are involved in translation of ultraviolet (UV) or visible radiation energy into phototoxic and/or photoallergic reactions in the skin. Phototoxicity presents in four major reaction patterns, depending on the target for photosensitization. Photoallergy is now confirmed as an immune system cell mediated photosensitization. Drug-induced photosensitivity is not necessarily a good reason for stopping therapy. Sunlight avoidance, appropriate protection with clothing, sunscreens, and drug dose reduction may allow continuation of treatment. However, future drug registration procedures may require more detailed testing both in vitro and in vivo, and good clinical trials for which suitable protocols are becoming available.

Animals↗
PubMed1990

Photosensitivity dermatitis and actinic reticuloid syndrome (chronic actinic dermatitis).

The photosensitivity dermatitis and actinic reticuloid syndrome (chronic actinic dermatitis) is a common eczematous photodermatosis of unknown aetiology that in severe form is an extremely disabling condition. It is unclear why males are particularly affected. Difficulties in diagnosis arise in patients who have perennial problems in whom clinical photosensitivity may not be volunteered. An additional problem for the clinician is the finding of contact allergy that is frequently multiple, which further complicates the clinical picture that may, in severe cases, present as an erythroderma or a pseudolymphomatous state. Patch testing and phototesting are the key investigations, with broad ultraviolet (UV) waveband sensitivity occurring as a dermatitis rather than a sunburn response. Contact allergy recognition and avoidance, along with photoprotective measures, are helpful in most cases. Photochemotherapy (PUVA) and systemic immunosuppression may be required in those patients who fail to respond. In some cases, spontaneous resolution follows after a number of years.

Chronic Disease↗
PubMed1990

Effect of dietary crude-protein type on fertilization and embryo quality in dairy cattle.

An experiment was conducted to determine whether balancing dietary crude protein for optimal rumen degradability would improve fertilization rate and quality of ova in lactating dairy cows. Thirty-eight Holstein cows in early lactation were fed 1 of 2 diets formulated to be isocaloric and isonitrogenous, containing 16% crude protein. Diet 1 contained 73% rumen degradable intake protein, whereas diet 2 contained 64% rumen degradable intake protein. The cows were induced to superovulate and were inseminated, and ova were recovered nonsurgically on postbreeding day 7. Ova were counted and classified as fertilized or unfertilized. Fertilized ova were scored as excellent, good, fair, poor, or degenerate. Unfertilized ova and poor and degenerate embryos were considered to be nontransferable ova and excellent, good, and fair embryos were considered to be transferable ova. There were no differences for mean number of fertilized, unfertilized, transferable, or nontransferable ova recovered from cows fed the 2 diets (P greater than 0.10). Mean percentage of fertilized ova recovered from cows was greater (P less than 0.05) in those fed diet 2, compared with diet 1. Mean percentage of transferable ova recovered from cows tended to be greater (P = 0.06) in those fed diet 2, compared with diet 1. More cows failed to yield transferable ova (P less than 0.05) when fed diet 1, compared with diet 2. Fertilization failure or early degeneration of embryos may occur in cows fed excess rumen degradable protein.

Animal Feed↗